NMRV-VS dual input worm gearbox with IEC motor flange

For Australian industrial machinery that must synchronise two drive sources or switch between a primary motor and a backup input without coupling hardware, the NMRV-VS dual input worm gearbox with IEC motor flange is the engineered solution. Featuring a hollow shaft output that mounts directly onto the driven machine shaft — eliminating a flexible coupling and its associated misalignment tolerance — and a dual-input design that accepts a standard induction motor, stepper motor, or servo drive on one side while retaining a secondary shaft input or coupling port on the other, this NMRV gearbox achieves synchronisation of two or more equipment trains from a single reducer unit. Available in ten frame sizes from NMRV 025 to NMRV 150, with gear ratios from 7.5:1 to 100:1 and input power to 7.5 kW, the NMRV-VS is used by Australian manufacturers in Sydney, Melbourne, and Brisbane across packaging, automated assembly, and food processing lines. Supplied with full technical support from Ever-Power Worm Gear Reducer Co., Ltd. (Australia), 27 Harley Crescent, Condell Park NSW 2200.

Key Specifications & Parameters — NMRV-VS Dual Input Worm Gearbox

The following specification table covers all standard NMRV-VS frame sizes and key technical parameters, aligned with ISO 9001:2015, DIN 3975 gear quality standards, and IEC 60034 motor flange compatibility requirements.

What Is an NMRV-VS Dual Input Worm Gearbox?

The NMRV-VS is a variant of the standard NMRV right-angle worm gearbox, distinguished by two key design differences: a dual input configuration and a hollow shaft output. The “VS” suffix designates the hollow shaft (VS = Vuoto Shaft in Italian gear industry terminology, carried forward as an international naming convention).

In the dual input design, the worm shaft extends beyond the housing on both ends. One end accepts the primary motor — mounted directly to the housing via a standard IEC B14 or B5 flange without requiring a coupling, which eliminates the most common source of worm gearbox alignment errors. The opposite end of the worm shaft is accessible for a second input source: a hand-wheel, encoder, secondary motor, magnetic brake, or stepless speed changer. This arrangement enables two or more machines to be operated synchronously from a single reducer, a design requirement frequently encountered in printing, dyeing, and web-handling machinery across Australian manufacturing plants in Melbourne and Sydney.

The hollow shaft output provides a direct bore mount onto the driven machine shaft, locking engagement via a key and setscrew. This eliminates the need for a driven-side coupling, reduces the machine envelope by typically 80–120 mm in the axial direction, and removes one additional alignment interface. A torque-arm bracket kit is included to react the housing rotational moment against the machine frame.

The worm wheel in NMRV-VS units is produced from a thickened tin-bronze specification — the wheel blanks are up to 15% wider than equivalent standard-specification NMRV worm wheels — providing measurably higher impact strength and crack resistance. This is confirmed against AGMA 6034 bronze gear material requirements and is particularly relevant in applications involving frequent start-stop cycles or moderate shock loading, common in Australian bottling, canning, and assembly line environments.

NMRV-VS Output and Input Configuration Options

The NMRV-VS is available in a matrix of input/output configurations. The following table identifies the standard variants and their principal application use-cases:

Manufacturing Quality: Thickened Worm Gear & Premium Material Specification

The NMRV-VS series differentiates itself from standard-specification NMRV imports through a deliberate upspecification of the worm wheel material and dimensions. The manufacturing process reflects the following quality commitments:

• Thickened Worm Wheel: Standard copper-alloy worm wheel blanks are 10–15% wider than the nominal DIN 3975 minimum face width for the frame size. This additional width distributes tooth load over a larger contact area, reducing Hertzian contact stress by approximately 10–15% and extending expected worm wheel wear life proportionally.
• High-Copper Bronze Alloy: The worm wheel material specification uses an elevated-copper tin-bronze with higher copper content than the minimum Grade C90700 (per ASTM B427) or equivalent, achieving Brinell hardness HB 90–110. This produces better impact strength and crack resistance compared to standard CuSn10 alloys used in many competing NMRV products.
• 20CrMnTi Worm Shaft: The worm shaft is machined from 20CrMnTi alloy steel bar, carburised to a case depth of 0.8–1.2 mm, and quenched to HRC 58–62 core hardness before precision cylindrical grinding and thread-form grinding. This heat treatment sequence delivers a worm mesh hardness ratio (steel worm vs. bronze wheel) of approximately 5:1, which is the optimal ratio for maximising worm wheel life per AGMA 6034.
• SKF/NAK Viton Oil Seals: The radial lip seals at both input shaft extensions and the output hollow shaft are Viton (FKM) compound, providing operating temperature resistance to +120 °C and chemical resistance to gear oils, synthetic lubricants, and mild cleaning agents used in Australian food and pharmaceutical plant washdown procedures.

How to Select the Right NMRV-VS Dual Input Worm Gearbox

Selecting an NMRV-VS for a dual-input or hollow shaft application involves several additional considerations beyond standard NMRV selection. Follow this step-by-step guide used by Ever-Power’s engineering team:

1. Define Your Synchronisation Requirement: Establish how many driven machines must be synchronised and whether both inputs will operate simultaneously or as primary/backup. If both inputs operate simultaneously, sum the input torques and ensure neither input motor is rated below the required share of the total output torque divided by the ratio.
2. Confirm Hollow Shaft Bore Compatibility: The hollow shaft bore diameter must match or be bored to match the driven machine’s solid shaft diameter. Standard bore diameters are available from 15 mm (NMRV 025) to 60 mm (NMRV 150). Specify the bore diameter and required key dimensions when ordering.
3. Select Ratio for Each Input Scenario: Since both inputs share the same ratio, the output speed is fixed by a single ratio for both input configurations. Ensure your secondary input device (brake, hand-wheel, etc.) is compatible with the input speed range — at a ratio of 50:1 and 1,450 rpm motor speed, the worm shaft runs at 1,450 rpm. A secondary hand-wheel will turn at 1,450 rpm if operated simultaneously with the motor, which could be hazardous. Engineering a disconnect or clutch in the secondary input is recommended for operator safety per AS 4024 guarding standards.
4. Size the Torque Arm: The hollow shaft output generates a housing reaction moment that must be absorbed by the torque arm and its attachment to the machine frame. Calculate the maximum output torque and specify the correct torque arm length and pin diameter from the series datasheet.
5. Specify IEC Motor Flange Size: Standard IEC flange sizes 56B14 through 90B5 are stocked. Confirm your motor’s IEC frame designation and ensure it matches the flange option available for your chosen NMRV-VS frame size. Non-standard flanges are available as custom options.

Compatible Accessories We Also Supply: Torque arm kits, hollow shaft bore extensions, IEC motor adaptors, electromagnetic clutch/brake assemblies, output shaft couplings, and mounting foot brackets. Contact us at Contact Us for a combined supply quote.

Applications of the NMRV-VS in Australian Industrial Machinery

The NMRV-VS’s dual-input design and hollow shaft output address a specific set of machine engineering requirements that are frequently encountered across Australian manufacturing operations:

• Packaging & Labelling Lines (Sydney, Melbourne): Web-tension-synchronised systems where two conveyor belts or rollers must run at precisely the same speed benefit from the NMRV-VS dual input — both drives share a common worm shaft, mathematically guaranteeing velocity synchronisation rather than relying on closed-loop electronic speed matching.
• Printing & Screen Printing Machinery: Feed rollers and take-up spools in screen printing machinery require synchronised drive. The hollow shaft mount eliminates the coupling compliance that can introduce registration errors in high-precision printing at up to 60 m/min.
• Automated Assembly Lines (Brisbane, Adelaide): Shuttle and indexing mechanisms that need motorised drive during normal operation and manual advance during tooling changes use the VS-K configuration — the secondary hand-wheel input allows safe manual indexing with the motor disconnected.
• Dyeing & Textile Finishing (Geelong, Melbourne): Fabric guides, stenter frames, and tension rollers in dyeing machinery commonly require geared synchronisation of multiple roll drives. The NMRV-VS’s hollow shaft eliminates the inline shaft coupling that is a major maintenance point in wet, chemically aggressive dyeing plant environments.
• Fishery & Aquaculture Equipment (Tasmania, WA Coast): Net-hauling winches and tank-stirring agitators in aquaculture installations require the combination of self-locking (to hold load without power) and easy manual backup operation — both provided by the NMRV-VS with hand-wheel secondary input.

Global Markets & Regulatory Compliance for the NMRV-VS Series

The NMRV-VS is one of the most widely specified dual-input worm reducers in international industrial machinery markets. Countries with the highest procurement volumes for this series include Australia, New Zealand, the United Kingdom, Germany, Italy, Brazil, and Southeast Asian markets including Vietnam and Thailand — reflecting the wide adoption of IEC motor standards in these regions, which the NMRV-VS directly addresses with its IEC-normalised input flange.

For Australian buyers, relevant compliance and standard references include:

• ISO 9001:2015 — Manufacturing quality management system covering all production stages
• IEC 60034 — Motor flange dimensional standards (B5/B14) confirmed for all available input flange options
• DIN 3975 — Gear quality specification for worm gear profile accuracy and surface finish
• AGMA 6034 — Practice for enclosed cylindrical wormgear speed reducers and gearmotors, used as design reference for rated torque and thermal power calculations
• AS 4024.1 — Australian Standard for machinery safeguarding, referenced for secondary input shaft guarding recommendations

RoHS compliance is maintained for all painted and coated surfaces. Units destined for food-contact adjacent applications can be supplied with NSF H1-registered gear oil (food-grade lubricant) pre-filled at factory, on specific request at time of order.

Customer Reviews — NMRV-VS Dual Input Worm Gearbox

Why Choose Ever-Power for NMRV-VS Dual Input Worm Gearboxes in Australia?

Ever-Power Worm Gear Reducer Co., Ltd. (Australia) at 27 Harley Crescent, Condell Park NSW 2200 maintains one of Australia’s most comprehensive NMRV-VS stock holdings, covering all ten frame sizes in the most common ratio and bore configurations. Our engineering team provides free application review — submit your motor frame size, output shaft diameter, required ratio, and duty cycle and receive a written recommendation within one business day.

As an Australian-based supplier with direct manufacturer relationships, we can offer OEM labelling, volume pricing for quantities above 10 units, and technical documentation in Australian English for compliance records. Visit our About Us page to learn more about our team and supply capabilities. Additional technical resources are available at worm-gearbox.top.

Frequently Asked Questions — NMRV-VS Dual Input Worm Gearbox